In ( DEF ), angle (F ) is a right angle. The hypotenuse is (DE = 25 , cm ) and one of…

MATHEMATICS · Multi-part · CBSE · Mathematics · Introduction to Trigonometry · Introduction to Trigonometry

Problem

\triangle DEF

, angle

F

is a right angle. The hypotenuse is

DE = 25\,\text{cm}

and one of the perpendicular sides is

EF = 7\,\text{cm}.

(i) Determine the length of the third side

DF

. (ii) Find

\sin E

\cos E

and

\tan E

. (iii) Show that

\sin^2 E + \cos^2 E = 1

for this triangle.